基于智能模糊PID控制的无人机飞控研究

Research on UAV Control Based on Intelligent Fuzzy PID Control

研究了一种有效的无人机稳定飞行姿态的方法。根据多旋翼无人机垂直、左右、前后运动和偏航运动的受力和运动原理,探索构建数学模型,选定合适的参考坐标系,选择四元数法用作描述四旋翼无人机姿态的数学方法,在描述多旋翼无人机的运动方式时,用横滚角、俯仰角和偏航角来验证关系,同时作为后续姿态控制的输入量。推理机体坐标系与导航坐标系两者互相转换时的变化矩阵,建立非线性动力模型,以互补滤波算法与扩展卡尔曼滤波算法为基础,将采集到的数据进行融合估算,结合串级PID控制器,以其作为框架,内部加上智能模糊控制理论,可以对PID参数的3个值Kp、Ki、Kd进行实时调节,使无人机具有更好的鲁棒性,当遇到突发情况时,飞控可以智能地调节参数,使无人机快速趋于稳定。采用MATLAB/Simulink仿真的结果表明,经过优化调节之后的模糊控制PID参数可以很好地调节无人机的姿态角速率和控制无人机的位置反应速率,提高无人机的稳定性。

An effective method for stabilizing the flight attitude of unmanned aerial vehicles(UAV)is studied.According to the force and motion principles of vertical,roll,pitch and yaw flight of quad rotor UAV,the mathematical model is established,the appropriate reference coordinate system is selected,the quaternion method is adopted as the carrier to describe the attitude of quad rotor UAV,and the relationship between quaternion and attitude Euler angle in the space coordinate system,namely roll angle,pitch angle and yaw angle,is constructed as the input of subsequent attitude control.The transformation matrix is inferred when the airframe coordinate system and navigation coordinate system are converted,a nonlinear dynamic model is established,combining the complementary filtering algorithm and the extended Kalman filtering algorithm to fuse and estimate the collected data,combining the cascade PID controller,taking it as the frame,and adding the intelligent fuzzy control theory internally,the three values Kp,Ki,Kd of the PID parameters can be adjusted in real time,In this way,the UAV can have better robustness,and the flight control system can intelligently change parameters according to the actual flight situation of the UAV to achieve fast and stable control.Simulations on MATLAB/Simulink show that the optimized fuzzy control PID parameters have good control ability for attitude angular rate of four rotor UAV and better position control for UAV.